Austrian Journal of Technical and


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Scopus, Web of ScienceAustriya-11-12,2019 (2) - копия

Key words: Mo concentrate, cinder, kaolin, organic polymer, granulation. 
Introduction.
Technology of production of the pyrite cinders 
of molybdenum middlings at JSC “Almalyk 
GMK” [1] includes the steps of: mixture 
granulation (composition: Mo-concentrate 
90%, kaolin 10%), firing of pellets at 600 °C 
to 
oxidize 
sulfide 
minerals 
and 
to 
recover rhenium oxide. As a result of the 
dilution of the original Mo concentrate with 
kaolin 
there 
is 

“dilution” 
of the pyrite cinders upon molybdenum. In this 
context, the search of pellet-forming scheme 
that minimizes this rate is the actual problem. 
The 
data 
revealed 
that 
if 
we 
use 
Objective: To provide such a binder for JSC 
“Almalyk GMK”. Its requirements: it should 
not contain any “technological poisons” (such 
as phosphates) adversely affecting the 
redistribution of cinder: leaching, sorption 
of Mo (VI) ions, hydrogen reduction to metal, 
sintering rods. Tasks: to compare the 
hydrophilic, 
strength 
and 
technological 
properties of binders: kaolin and alternatives to 
it of organic and organic-mineral nature, being 
in the composition of pellets and cinder of Mo 
concentrate. 
Subjects and methods. Batch of Mo 
concentrate ranulation was prepared using 



11-12, 2019 
42 
the traditional composition of the batch 
mixture in the production of cider, the 
proportion of Mo in the granules is reduced to 
4%. In addition, it is known that the 
presence of kaolin in cinder makes difficult to 
sublimate rhenium oxide and impairs its 
commodity indices such as the fullness of 
ammonia leaching, Au and Ag extraction from 
a cake. To improve these technical and 
economic indicators was an idea to replace
completely or partially, kaolin with organic 
binder to be burned at a sintering of Mo-
concentrate and causing no dilution of 
the product.
Limiting wetting angles of the batches 
prepared on Moconcentrate base in compare 
with 
few 
reference 
data 
[6] 
are offered in From Table 1 it is revealed that 
the sample Nr 1 is identified as being 
hydrophobic material. Decrease of its 
hydrophobicity was facilitated with binders 
allowing it to be granulated. Selection of the 
best of them for the role of alternative to kaolin 
was intended to experiment aimed at a 
comparison 
between 
the 
strength 
of 
granules with a diameter of 3–5 mm, made of 
MoS2-containing batch materials with binders, 
after their dryingfiring at 20, 250, 600 °C. 
(Tabletka). In manufacture of candle end of 
Mo middlings the requirement to the durability 
of granules is empirically revealed, adjustable 
by a mode of balling in dish nodulizer of own 
design, with diameter of a plate made of a 
stainless steel equal to 2 m, as well as by batch 
composition,%: Мо-concentrate 92–90, kaolin 
8–10. The corner of an inclination of a dish
speed of its rotation and submission of a batch 
with water, time of balling were selected too 
empirically, aspiring to the optimum size and 
durability of the granules. At understating of 
the kaolin maintenance in granule’s batch 
mixes their resistance to abrasive wear on a 
way to a furnace fell, at their overestimate — 
permeability of oxygen in granules (О2 is 
necessary for oxidation of molybdenite up to 
trioxide of Мо) was blocked: in both cases the 
content 
of 
sulfur 
in 
the 
candle end exceeded norm of State standard 
2677–78.So one of the research’s problems 
was the quantitative description of the above-
stated 
requirement 
empirically 
revealed by the industry to durability of 
bindering: kaolin, bentonite, liquid glass LG, 
Na-carboxymethylcellulose 
(NaCMC), 
polyvinyl acetate (PVA), sulfonated cellulose 
[2;3], hydrolysis product of waste of 
production of polyacrylonitrile fiber SC. Their 
composition (binder content,%; Mo  

(J,%) 
was 
determined 
as 

percentage of reflex expressed at the 
maximum. Results and discussions. The Mo 
concentrate’s composition supplied to the 
granulating 
was 
the 
following, 
%: Mo 38; Re 0.7; Cu 2.5; P 0.009; Sb 0.025; 
WO3 0.05;S 25.2; SiO2 10.8; humidity 0.42; 
peculiar to Mo concentrate quantities of Au 
and Ag presented there too. 
7 (bentonite 2%, PVA 2%), 8 (bentonite 2%, 
sulfonated cellulose 2%). 9 (SC 1%), 10 (SK 
1.5%, LG 1.5%),11 (bentonite 2%, SC 1.5%, 
LG 1.5%), 12 (kaolin 2%, SC 1.5%; LG 1.5%), 
13 (LG 3%); 14 (bentonite 2%,CMC 1.5%); 15 
(bentonite 2%, SC 0.5%); 16 (kaolin 
2%, SC 0.5%); 17 (bentonite 1%, CMC 0.5%), 
18 (bentonite 1%, SC 0.5%). 
Limiting wetting angle of batch material 
compacted under a pressure of 20 MPa (
∅ 12, 
height: 4 mm) wasdetermined from the profile 
of water droplets thereon [4]. The granules 
were obtained in the disc pelletizer, then dried 
at 20 °C, 24 hr. Their crushing strength was 
evaluated with the following methods: 1) of 
integrity of the granules dropped from a height 
of 2 m onto concrete; 2) of compression 
fracture. Their comparison revealed allowable 
strength criterion: F ≥ 1.2 MPa. The content of 
elements 
in 
the 
raw 
materials 
and 
technological solutions was determined by 
ultimate analysis carried by AAS "Perkin-
Elmer" PE 3030V with a flaming atomizer, 
and Aligent 7500 ICP MS. Thus, Au and Ag in 
the 
samples 
were 
determined 
at 
wavelengths of 242.8 and 328.1 nm with 
preconcentration extraction in a toluene 
solution of sulfide oil at a ratio of 
organic / aqueous phases = 1/10, respectively. 
IR absorption spectra were recorded in the 
range of 400-4000 cm-1 with AVATAR-360 
spectrometer Nico let. Thermograms were 
recorded by derivatograph Paulik Erdey at 
gradient 10 degrees per min, sample weight 
0.200-0.250 g, in corundum crucible 
∅ 10 mm, 
with T-900, TG-200, the DTA-1/10, DTG1/20 
sensitive galvanometers and Al2O3 as a 



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